you have some blow by, most likely piston rings but you may wanna check the pcv valve if it's clogged or if it's good it'll rattle. that releases your positive crankcase pressure and if it's clogged up it'll find a way to release crankcase pressure ie past the piston rings thus creating your scenario and/or other oil leaks....i'd be a happy camper if i could fix my blow by with a pcv valve and 4 quarts of 20w-50. check that pcv valve